When I play Minecraft Java in a single player world and run Minecraft Plus (screen saver) because I don't interact with the pc for a while. When I'm not in the Esc menu or chat. And I press a button to stop the screen saver. Then I can't interact with the cursor in Minecraft. To solve the problem, I just have to change the display on which Minecraft is running to another one.
I've only tested it with version 1.16.4.
Please provide some screenshots or videos of this issue occurring whilst the F3 debug screen is enabled.